A top leader of Tehreek-e- Taliban's Jamaat-ul Ahrar faction and the militant group's former spokesman has surrendered himself to the security forces, Pakistan army said today.

Ehsanullah Ehsan is a known face of violence in Pakistan as former spokesman of the Tehreek-e-Taliban Pakistan (TTP), who joined Islamic State linked Jamaat-ul-Ahrar outfit after 2014 military operation 'Zarb-e-Azb'.

Military spokesman Major General Asif Ghafoor said that it was big achievement for Pakistan that "our biggest enemies" were surrendering.

"I want to take this opportunity to announce that Ehsanullah Ehsan, the former spokesperson of the TTP and a leader of the Jamaat-ul-Ahrar, has turned himself into our security agencies," he told reporters.

He did not share more details about the surrender.

The official said operation 'Radd-ul Fassad' launched in February against militants was going on successfully and no militant groups would be spared.

He said 15 major operation were carried out as part of it and 108 militants were killed and 4,510 suspects arrested.

"The people, the state and the institutions of Pakistan have made considerable progress in the betterment of the country's security situation. We will completely destroy militancy," he said.

He also said the military courts had decided 274 cases and awarded death sentence to 161 militants.

He said border with Afghanistan was being fenced to stop infiltration of militants from across the border.

The spokesman also alleged that India was repeatedly violating the ceasefire agreement in Kashmir and its violation of LoC has increased.